Who Is Will Halstead’s Father Pat on ‘Chicago Med’?

On the Chicago Med episode ‘Generation Gap’, Dr. Will Halstead (Nick Gehlfuss) has treated many patients over the years without hesitation. But when Will sees his father in the ER, he has to collect himself. Pat Halstead has been discussed on the show — Will’s brother, detective Jay (Jesse Lee Soffer) crosses over from Chicago P.D. — but this is the first time Chicago Med fans get to see the obstinate man in person.

Halstead’s father is portrayed by Louis Herthum. He’s known for his roles on Westworld (Peter Abernathy), Longmire (Omar), True Blood (JD), and Murder, She Wrote (Deputy Andy Brown), among others. Fun fact: Herthum made his acting debut in the 1982 film The Toy with Richard Pryor and Jackie Gleason (as the Man in the Box). Chicago Med airs Thursdays at 9pm on NBC.